JP2004-271902A discloses an example of a monitor camera apparatus including an image processing apparatus for performing an image processing on an image obtained during photographing by imaging light on an image-pickup element such as a charge coupled device (CCD) or complementary metal oxide semiconductor (CMOS) sensor. The monitor camera apparatus is configured to record a picture obtained by the photographing onto a video cassette recorder.    Patent Document 1: JP2004-271902A (refer to description in ABSTRACT and the like)
In a case where, for example, a monitor camera apparatus is used for monitoring and photographing an inside of an uninhabited office during nighttime hours, the photographing is continuously performed on a subject that is not changing as time elapses, for example, an immobile stationary object such as an office desk. In the case of monitoring and photographing such a subject inside the uninhabited office, a particularly necessary picture among pictures obtained by the photographing is a picture obtained when there is an abnormality, namely, a change within a photographed range being monitored. Examples thereof include a picture obtained when there is a change in the subject such as when a person or the like illegally enters the photographed range or when lighting equipment within the photographed range is turned on.
However, even in a case where only a scene in which the subject is changing is to be watched by reproducing photographed contents recorded on a video cassette recorder on a monitor, the photographed and recorded contents need to be watched from the start to the end to confirm whether or not the subject is changing. This raises a problem that a long time is required for a work of confirming whether or not there is an abnormality, namely, a change within a monitored range. In particular, in a case where the picture is obtained by the photographing using a wide-angle photographic lens, the photographed range is wide, and a wide-range picture is displayed on the monitor. This raises a problem that a change in details of the subject is hard to find, and that contents thereof are also hard to confirm.
It is therefore an object of the present invention to provide an image processing apparatus, a camera apparatus, and an image processing method in which even if an image is obtained by photographing a wide range by a wide-angle lens, when there is a change in a subject, a picture in which a changing part thereof is enlarged makes it possible to easily confirm whether or not the subject is changing and also possible to easily confirm contents of the changing part.